Oxygen delivery systems that include nasal cannulas are well known in the art. Examples of such prior art systems include U.S. Pat. Nos.: 6,328,038 B1; 6,298,850; 5,682,881; 5,636,630; 5,438,979; 5,271,391; 5,117,818; 5,025,805; 4,836,200; 4,808,160; 4,753,233; 4,739,757; 4,699,139; 4,422,456; 4,406,283; 4,156,426; 4,106,505; 3,802,431; 2,868,199; 2,763,263; and 2,168,705.
While nasal cannulas are a convenient method of supplying a patient with oxygen enriched gases, it would be highly desirable to have a new and improved oxygen delivery system that includes a nasal cannula that is easily adjusted for the comfort of the patient and that is not prone to falling off the face of the patient.